Custom Shapes Meet Demands of Lens Annealing


The eyeglass manufacturer's process called for a carousel style annealing furnace requiring an arc shaped "tunnel" heater to anneal out stress in glass lenses.


This unique requirement was met by ceramic fiber heaters produced in custom shapes. Watlow's ability to custom mold ceramic fiber heaters into concave and convex shapes produced outside and inside walls of a 270 degree curved tunnel heater. High performance 60 volt, 600 watt 12.5 W/in2 (1.9 W/cm2) heaters, with increased emissivity hot face coating, easily met the demand for production throughput.